1. Technical Field
The present disclosure relates to a waveform similarity calculation method for calculating a similarity between waveforms indicated by time series data. Particularly, the present disclosure relates to a waveform similarity calculation method which can accurately extract time series data substantially similar in waveform.
2. Description of the Related Art
Historical data which are past time series data collected at a certain sample interval from respective portions of a plant are stored in a field control system, a plant information management system, various recorders, etc. These historical data are analyzed and put to use for understanding plant's behavior or improving plant's operation. Particularly, when the same operation has been performed before, the historical data at that time can be referred to for the present operation. The following method can be conceived as a method for extracting the past operation.
(1) A person searches for a date and a time of close operation conditions from a logbook and refers to historical data at that time.
(2) The person views the historical data which are sequentially displayed in a graph, and searches for a close operation part.
(3) The close state is expressed by some kind of conditional expression and retrieved by use of a computer.
3. Citation List